Originally Posted by
Badger6
I've had enough mechanical failure in my life to know that going cheap is not a good bet.
Sure, but this isn't necessarily "going cheap." The derailleur I'm referencing sells for $70-$80, which is in the price range between 105 and Ultegra.
I'm also well aware that the benefits of low gearing (meaning low ratios have limits).
The scope of this discussion doesn't provide much clarity as to where those limits are, though. Without knowing the OP's legs and the gradients they're dealing with, it's impossible to know what's reasonable. For instance, suppose someone is able to smoothly and powerfully handle a 250m 8% hill in their 36-28, so they use an 11-28 cassette. What would they need to pedal just as effectively if the hill was 12% instead? 50% more slope means 50% lower gearing to have similar torque and cadence, which means a 42T cog if the cranks are kept the same.
This kind of stuff isn't necessarily hypothetical. Loads of hills in my area are like that. Heck, there's one gravel road near me which has a 1-mile stretch averaging just shy of 16%.
(Really, I only get away with a 32T cog because I also have a 24T inner chainring. But that's not widely available for modern road setups, which is a big part of why people in mountainous areas are being forced into huge cassettes. I agree that it's often non-ideal, but it's often the path of least resistance for a viable solution within the current market.)
that refuses to accept as an acceptable substitute for training and conditioning
"Training and conditioning" is an astronomically larger commitment compared with changing components, and there are practical limits for any given person, both in terms of what their body can do and in terms of what they want out of their cycling commitments. And it's not like these approaches are mutually exclusive, gearing versus fitness isn't an either-or situation.